This invention relates to an improvement on a block to be used for a revetment, in which a plurality of such blocks are connected one another and laid in tiers on the slopes of seashores and rivers so that safety for walking thereon is enhanced.
Methods for laying the blocks on the slopes of seashores and the like are known. One conventional method is that square-shaped blocks having the generally same thickness are used and mortar is filled in the jointing portions formed between adjacent blocks laid. Another conventional method is that each block is provided with two or more through holes formed thereon in parallel relation, and such blocks are laid in parallel relation and connected one another by inserting an iron wire into each of the through holes intercommunicated.
The first-mentioned method in which mortar is filled in the jointing portions has the shortcoming in that the blocks laid are separated apart due to sinking of the ground and the like and the blocks are disconnected one another to permit the ground to be exposed therefrom. Thus, the blocks lose their own function. On the other hand, the second-mentioned method in which an iron wire is inserted into the through holes has the shortcoming in that the blocks laid are displaced one-sidedly due to the change of the ground and the blocks are separated apart one another and the ballasts thereunder are sucked out to form a hollow ground, thus disabling to construct a strong revetment.
The present invention was accomplished in order to solve the above-mentioned problems inherent in the prior art.